The design of nanosheets interlayer between the substrate and polyamide layer has attracted growing attention to improve the performance of thin-film composite membranes. However, the membrane size is limited by current fabrication methods such as vacuum filtration. Herein, a high-performance MXene (Ti3C2T x ) interlayered polyamide forward osmosis (FO) membrane is fabricated based on a combination of a facile and scalable brush-coating of MXene on nylon substrates and the interfacial polymerization process. The as-prepared FO membrane shows high water permeability of 31.8 L m–2 h–1 and low specific salt flux of 0.27 g L–1 using 2.0 mol L–1 sodium chloride as the draw solution. This is attributed to the adjustment of substrate properties and the polyamide layer by coating of MXene as well as the facilitation of water transportation by the interlayer distances between Ti3C2T x . The membrane also exhibits a good organic solvent forward osmosis performance with high ethanol flux as 9.5 L m–2 h–1 and low specific salt flux of 0.4 g L–1 using 2.0 mol L–1 lithium chloride as the draw solution. Moreover, the MXene interlayered FO membrane demonstrates a feasible application in real seawater desalination and industrial textile wastewater treatment. This work presents an effective approach to fabricating nanomaterials interlayered FO membranes with superior performance for both desalination and organic solvent recovery.

of the most attractive inventions because they have dramatically improved our daily lives by enabling portable electronics, the onset of electronic mobility and electrical vehicles. [1] With the development of materials science, anionic redox chemistry, typically O redox, has enabled more energy storage than the traditional electrochemical reactions, in which the energy and power density are solely determined by the cation redox reaction of transition metals. [2] On the other hand, the rapid growth of lithium consumption leads to continuously increasing demand for lithium. Considering the uneven distribution of lithium resources, the inherent drawbacks of lithium supply and demand are difficult to overcome. [3] Therefore, an alternative to lithium must be considered, especially for large-scale energy storage applications in the foreseeable future.The Na-ion battery, which has a reaction pattern comparable with that of the Li-ion battery, is one of the promising alternatives because of its low cost and the abundance of sodium resources. [4] Currently, the study of Na-ion batteries is focused on improving their energy density. Considering the successful study of Lirich materials, one of the possible solutions to improve the capacity of Na-ion batteries is to develop Na-rich materials. It is very important to involve reversible O redox and expand the material series from the material design point of view.Recent research disclosed, the increasing of the Li(Na) content within layered structure materials can effectively influence the local atom coordination around oxygen atoms which could improve O redox upon cycling and lead to a higher capacity. [5] As demonstrated by Tarascon and Ceder et al., increasing the Li(Na) ratio can shift the O 2p nonbonding band gradually up near the Fermi level. This labile nonbonding O offers an extra way for electrons to move away, hence increasing the capacity by triggering an extra redox process. [2e,5c,6] This explanation has been successfully applied to Li 2 MnO 3 Li-rich materials [7] and is widely agreed upon. Benefitting from the established Li 2 MnO 3 Li-rich prototype, Li-rich material development has highly improved during the past decades, achieving additional capacity. [8] For the counterpart Na-ion battery design, although anionic redox was recently realized in the Mn-based To improve the energy and power density of Na-ion batteries, an increasing number of researchers have focused their attention on activation of the anionic redox process. Although several materials have been proposed, few studies have focused on the Na-rich materials compared with Li-rich materials. A key aspect is sufficient utilization of anionic species. Herein, a comprehensive study of Mn-based Na 1.2 Mn 0.4 Ir 0.4 O 2 (NMI) O3-type Na-rich materials is presented, which involves both cationic and anionic contributions during the redox process. The single-cation redox step relies on the Mn 3+ /Mn 4+ , whereas Ir atoms build a strong covalent bond with O and effectively suppress the O 2 release....

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In this review, systematic overlook of recent research on anionic redox in SIBs is given, along with discussion of relative theories that explain the mechanism of activating and stabilizing anionic redox activity.

Layered oxides as the cathode materials of sodiumion batteries are receiving extensive attention due to their high capacity and flexible composition. However,t he layered cathode tends to be thermodynamically and electrochemically unstable during (de)sodiation. Herein, we propose the pinning effect and controllable pinning point in sodium storage layered cathodes to enhance the structural stability and achieve optimal electrochemical performance.0%, 2.5 %and 7.3 %transitionmetal occupancies in Na-site as pinning points are obtained in Na 0.67 Mn 0.5 Co 0.5Àx Fe x O 2 .2 .5 %N a-site pinned by Fe 3+ is beneficial to restrain the potential slab sliding and enhance the structural stability,r esulting in an ultra-low volume variation of 0.6 %a nd maintaining the smooth two-dimensional channel for Na-ion transfer.The Na 0.67 Mn 0.5 Co 0.4 Fe 0.1 O 2 cathode with the optimal Fe 3+ pinning delivers outstanding cycle performance of over 1000 cycles and superior rate capability up to 10 C.

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Layered transition metal oxides as promising cathode materials for sodiumion batteries have been extensively studied to obtain superior electrochemical properties. Since the cationic redox materials have almost reached the theoretical capacity limits accompanied by the migration and disproportionation of transition metals, anionic redox counterparts have been extensively explored to obtain extra capacity. In this work, P2-type Na 0.67 [Li 0.21 Mn 0.59 Ti 0.2 ] O 2 is introduced, where manganese and oxygen synergistically undergo redox reaction reversibly. In situ X-ray diffraction (XRD) experiments indicate a highly stable lattice structure with an extremely small volume strain of 0.7% during cycles with no sign of phase transitions. The stable crystal structure demonstrates the suppression of manganese disproportionation which is common in the layered Mn-based cathode materials. Thanks to both cationic and anionic redox, this material can deliver a reversible capacity of 231 mA g −1 in the voltage range of 1.5-4.5 V and the high-voltage plateau can be maintained during subsequent cycles with splendid cycling stability.

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